The present invention generally relates to the field of internal combustion engines, and more specifically to an internal combustion engine having a cylinder head with an exhaust gas recirculation passage therein for routing exhaust gas back into the intake of the engine.
Environmental concerns about the discharge of combustion by-products into the atmosphere have caused many engine designers to focus on minimizing the discharge of certain materials from the engine. One by-product of concern are Nitrogen Oxides (hereinafter NOx), a gas, which is formed during the combustion cycle of the internal combustion engine. The degree of NOx gas formed during the combustion cycle is related to the temperature of the exhaust gas within the engine's combustion chamber.
Consequently, in order to reduce the quantity of NOx gas formed during the combustion cycle exhaust gas recirculation systems were developed. A typical exhaust gas recirculation system includes directing a portion of the exhaust gas from the combustion chambers through the intake manifold and back into the combustion chambers. As a result, the temperature of the exhaust gas within the combustion chambers is lowered to thereby reduce the formation of NOx gas.
The automotive industry is continually striving to improve the performance of the exhaust gas recirculation systems and to minimize the amount of space needed for the exhaust gas recirculation system. The present invention contributes to the advancements in the field of exhaust gas recirculation systems in a novel and unobvious manner.